Electric switch



Dec. 16, 1930. T. A. BOTH 1,785,068

' ELECTRIC SWITCH Filed Dec. 8, 1926 Patented Dec. 16, 1930 UNITEDSTATES PATENT OFFICE TON J'ES A. BOTH. OF STRATFORD, CONNECTICUT,ASSIGNOR TO THE CONNECTICUT ELEC- TRIC MANUFACTURING COMPANY, OFBRIDGEPORT, CONNECTICUT, A CORPORATION 1 OF CONNECTICUT ELECTRIC SWITCHApplication filed December 8, 1926. Serial No. 153,287.

This invention relates to electrical switches, particularly to a switchof the snap acting type, and has for an object to provide an 1mprovedstructure, especially for mounting the movable switch'contact, whichwill be much simpler in construction andmay be manufactured at a lesscost and which will be much less likely to break down and form a shortor ground than will the structures now generally employed.

With the foregoing and other objects in view, I have devised a switchconstruction some of the preferred forms of which are illustrated in theaccompanying drawing forming a part of this specification. In thisdrawlng,

Fig. 1 is a vertical section through the body of a switch showing theswitch mechanism in side elevation, and with portions broken away y tomore clearly show the construction.

Fig. 2 is a transverse section substantially on. line 22 of Fig. 1omitting the insulating body.

Fig. 3 is a side elevation of the movable switch contact and themounting therefor on an enlarged scale, a portion being broken away toshow the means for attaching the contact.

Fig. 4 is a front elevation thereof looking from the right of Fig. 3.

Fig. 5 is a detail section substantially on line 55 of Fig. 3.

Fig. 6 is a view similar to Fig. 3 showing a slightly difl'erentconstruction and means for mounting the contact.

Fig. 7 is an elevation looking from the right of Fig. 6.

Fig. 8 is a detail section substantially on line 88 of Fig. 6. 1

Fig. 9 is a side elevation of the movable switch contact. and itssupport, showing anthrough the tact taken substantially on line 12-12of- Fig. 14.

Fig. 13 is a section thereof substantially on line 13-13 of Fig. 12, and

Fig. 14 is a front elevation and a section of the contact line 14-14 ofFig. 12.

Referring to Figs. land 2 the switch mechanism is mountedin the usualbody 15 made of insulatingv material, such as porcelain. which carriesthe stationary contacts 16 and 17 to which the leads, not shown, fromthe house wiring system may be connected by the binding screws 18. Theswitch mechanism proper is mounted on a yoke 19 to which the body 15 isconnected and by which the device is mounted in the wall outlet box inthe usual manner. The yoke has spaced side members 20 extending into thechamber in the body and forming a frame or mounting for the movableelements of the switch. These side members each has a notch or shoulder21 in which the movable switch contact supporting member 22 is mountedfor rocking movement. In the present construction this member comprisesa flat plate having an opening 23 therethrough arranged with the edges24 on one side of this opening resting in the notches 21. Pivotallymounted at 25 is a rocking lever 26 which has a projecting handle 27either of metal or insulating material extending usual opening in thecover plate for operation of the switch. This lever includes a. plate 28having stop shoulders 29 at the opposite ends thereof to engage theinner wall of the yoke to limit the movements of the lever in oppositedirections, and this plate has a notch 30 in which is seated one end ofa compression spring 31, the other end of the spring engaging 9. lug 32on the opposite edge of the opening 23 in the support 22. It will beapparent that as the lever is swung up and down on its pivot theconnection with the of the mounting substantially on spring by the notch30 will swing that end of "the spring back and forth through the planeof the plate 22. During the movement from the lateral positions to theplane of this plate the sprlng is compressed, and as soon as the springpasses through the plane of the plate the force of-the compressed springwill swing the plate in the opposite direction about the pivot edges 24and shift the position of the switch contact member 33 carried by thisplate, and will thus shift it to and from eng azigement with thestationary contacts 16 and l 7 At the present time the common practiceis to make the switch contact supporting plate 22 of metal, and theswitch contact member corresponding to the member 33 is secured to thissupport by suitable rivets. It will be apparent that the switch contactmust be insulated from this support, and the usual prac' tice is to useinsulating discs or washers on the opposite sides of the plate andbetween the plate and the contacts, and also to use in sulating washersabout the rivets where they pass through the contact. It will be obviousthat under this arrangement the insulation for the rivets is covered upwhere it is out of sight and is difiicult to inspect, and besides thespace between the metal support and the contact is not great. Therefore,considerable difiiculty is experienced by the insulation breaking downforming shorts or grounds. Furthermore, such a construction is expensiveto assemble.

I have overcome these difficulties in the present construction byforming the movablecontact support 22 of a plate of suitable insulatingmaterial and so forming the switch contact 33 that it is directlyconnected and mounted on this support. By this arrangement there is nodanger of the insulation breaking down forming shorts or grounds to theswitch mounting, and the connection is open where it may be easilyinspected. Furthermore, the structure is greatly simplified so that itmay be manufactured and assembled I have found that the article known inthe trade as laminated bakelite is very satisfactory for this support,the term -bakelite being used to indicate any of the phenoliccondensation products of the type of which the true bakelite is only aspecific example. This article is composed of several sheets of fabric,usually cotton or linen, covered on both sides with the phenoliccondensation product which is then pressed together under high pressureand with the application of heat. When cool the article is very hard andtough, and I have found that the wearing of the edges 24 in the notchesor shoulders 21 is no more, and is in fact less. than where metal isused. In the dwrawings I have shown several specific ways of mountingthe movable switch contact 33 on the insulating plate or support 22.

In'Figs. 3, 4 and 5 the contact 33 is composed of a pair of spring metalplates 34 whiclr'extend transversely of the plate 22 and have. lugs 35which are bent laterally to engage the opposite sides of the insulatingplate 22 and receive one end thereof between them. The. elements arethen secured to the plate by means of a rivet 36 passed through theselugs and the plate.

In Fig. 6 to 8 the switch contact member comprises two spring metalplates 37, and

the support 38 corresponding to the supporting member of Fig. 1 to 5 isprovided with spaced openings 39. The contact plates 37 each have a palrof lugs 40 which are passed through these openings and merely bent overagainst the opposite surface of the support as indicated. It will beobvious that this is a very simple construction which may-be easilymanufactured and assembled and which will rigidly mount the contact onthe support.

In the form' shown in Figs. 9 to 11 the switch contact comprises a pairof metal plates 41 which at their central portion have lugs on theopposite sides thereof bent laterally transversely of the plane of theplates. The lugs 42 on the inner plate are somewhat shorter and closertogether than the lugs 43 'on the outer plate so that they may be nestedtogether, as shown in Fig. 11. The end of the insulating support 44 isseated between the lugs and has openings 45 therethrough into which thefree ends of the lugs 43 are bent to securely fasten the contact to thesupport.

In Figs. 12 to 14 the insulating support 46 corresponding to theinsulating supports of the other forms has adjacent one edge an oblongopening 47 which is contracted at its opposite ends to form inclinedside edges 48. The switch contact member comprises two spring plates 49which are of a width at their centers to pass through the opening 47 andare provided on the opposite edges thereof with notches 50. These platesare bowed somewhat and arranged with the concave sides together as shownin Fig. 13, so that their central portions tend to separate. Theseplates are inserted in the opening 47 by pressing the central portionstogether, then when in proper position they are released and the centralportions will separate under the resiliency of the members to theposition of Figs. 13 and 14, which will cause the inclined side edges 48to seat in the notches 50 in the contact plates. This will secure theplates to the support, but they may be easily removed by reversing thisprocess, that is, by pressing the central portions together to removethe notches 50 from the inclined wall 48 and then sliding the contactsfrom the opening.

invention is not limited to this particular shape of the support, as itwill be obvious it may be made in different shapes depending on the typeof switch mechanism which is to be employed. Whilein Figs. 4, 7,10 and14, I have shown a single switch contact mounted on this support it willbe obvious:

that a similar switch contact may be secured to the opposite end of thissupport for use in a double pole switch. In Fig. 10 I have shown thesupport 44 as provided with a separate set of openings45 for mountingthis second switch contact, and, of course, the same feature may be usedfor any of the other supports. I wish to particularly emphasize the factthat the rocking and movable support for the switch contact member is ofitself composed of insulating material and that the switch contactmember is directly secured to and mounted on this support, doing awaywith the necessity of providing separate insulating elements as isrequired for the constructions now generally employed for insulating thecontact member from the metal support, and also removing the liabilityof a short or ground from the switch contact to this support.

Having thus set forth the nature of my invention, what I claim is:

1. In an electric switch, a flat support comprising a plate composed ofinsulating material mounted to rock in a mounting about an edge of theplate as a pivot in a direction transverse the plane of the plate andhaving a transverse opening, a switch contact member mounted directly onsaid support to move therewith in a plane substantially normal to theplane of the plate, means extending into said opening to secure thecontact directly to said support, and means for rocking the support. v

2. In an electric switch, a frame having shoulders, a flat supportcomposed of insulating material having edges engaging said shoulders forrocking movement in said frame about said edges as a pivot and in adirection transversely of the plane of the support, said support beingprovided with a transverse opening, a switch contact member directlyconnected to said support to move therewith in a plane substantiallynormal to the plane of the support, means in said opening to secure thecontact to the support, and means for rocking said support.

3. In an electric switch, a frame, a contact support comprising a flatplate composed of insulating material mounted for rocking movements insaid frame in a direction transversely of the plane of the plate andprovided with a transverse opening, a switch contact member mounted onsaid support to move therewith and extending from the plate in a planesubstantially normal thereto, means in said opening to secure thecontact to the plate, and means for rocking the support.

4. In "an electric-switch, a movable contact support comprising a'flatplate of insulating material mounted to rock about an edge thereofin: adirection transverse the plane iiof thei'plate,fia switch contact'membercomprising a spring plate having lugs passing through the. plate: andfolded. against-the plate to'secure the contact thereto, and means forshifting the plate to operate the switch;

' 5. In anelectric switch, a movable contact support comprising a plateof insulatingmaterial provided with an opening therein, a switch contactmember comprising asubstantially flatmember extending from oppositesides of theplate in a plane substantially normal to the plane of theplate and having a lug passing through said opening and folded over onthe opposite side to secure said member to the plate, and means forshifting the plate to operate the switch. I

6. In an electric switch, a movable contact support comprising a plateof insulating material havin an opening therein, a switch the plate andhaving a pair of spaced openings, a switch contact member extendingtransversely of the plane of the plate and having lugs extending throughsaid openings and folded over against the surface of the plate to securethe member thereto, and

means for moving the plate to operate they switch.

8. In an electric switch, a movable support comprising a plate ofinsulating material having a pair of spaced openings, a switch contactmember comprising a pair of metal plates arranged side by side andextending transversely of the support, said plates eac having lugsextending through said openings and folded over against the surface ofthe support to secure the plates thereto, and.v

means formoving the support to operate the switch.

9. In an electric switch, a frame having spaced side members providedwith notches,

a movable switch contact support comprisinga plate of insulatingmaterial having an opening therethrough and with the edges at one sideof the opening seated in the notches to form rocking pivots for theplate, said plate being also provided with a second opening, a switchcontact member extending transversely of said plate and having securmgmeans integral therewith to enter said second opening and engage theplate to secure the contact member thereto, and means transverse formoving the plate to operate the switch.

10. In an electric switch, a frame, a contact support comprising a flatplate composed of insulating material mounted forrocking movement insaid frame in a direction transversely of the plane of the plate andprovided with a transverse opening, a switch contact member mounted onsaid support to move therewith and extending from the plate in a planesubstantially normal thereto, means integral with said contact memberextending into said opening to secure the contact to the plate, andmeans for rocking the support.

In testimony whereof I affix my signature.

TONJES A. BOTH.

